SPF: Legacy record type in use

What this means

A legacy SPF record (type 99) was found in your domain.

Why this is a problem

The SPF standard has deprecated use of the legacy SPF type record and requires use of a standard TXT record instead.

Email delivery which relies on passing SPF checks may not be delivered successfully to intended recipients as mail servers may not process a legacy record. 

Your SPF configuration may be more prone to misconfiguration due to obsolete records in use.

How to check if the problem is there

Check your DNS zone for SPF (type 99) records.

You might want to use the following online tools to check for this issue:

• National Cyber Security Centre’s (NCSC) check your email security tool
• Hardenize’s domain report tool

How to fix this

Publish your SPF record as a TXT type instead of the legacy SPF (type 99) DNS record.

If you have both a TXT and ‘SPF-type’ SPF record, ensure that any changes are merged appropriately into the TXT record prior to deleting the SPF-type record.

Ensure that the merged record does not contain any duplicate entries, and does not exceed any length or lookup limitations.